"What he looks like, in a sense, is very incidental to him," she said. "He really doesn't dwell on that very much.

"What he dwells on is the reaction that people have to him. Because all he wants is to be an ordinary kid. But he really can't, because he'll always have people staring at him and reacting to him in a certain way."

Wonder has sold over 2 million copies and won a host of awards, as voted by the young audience it was written for. The movie comes to cinemas next April.